CVE-2026-108953
HighCVSS 7.8Exploitation Probability (EPSS)
Elevated risk54th percentile - higher than 54% of all known CVEs
Summary
mac-shell-mcp before 2.0.0 contains an OS command injection vulnerability that allows MCP clients to bypass the command whitelist by injecting shell metacharacters into execute_command arguments. Attackers or malicious prompts can call a safe command such as pwd with arguments like ';' to run forbidden commands as the server user without approval.
Risk Assessment
An attacker can execute arbitrary system commands with the server user's privileges, potentially leading to full system compromise, data theft, or further escalation. The risk is high because bypassing the whitelist requires no user interaction.
Recommendation
Upgrade mac-shell-mcp to version 2.0.0 or later, which fixes the vulnerability. Additionally, implement strict argument validation and avoid passing user input directly to the shell.
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Original NVD description (English source)
mac-shell-mcp before 2.0.0 contains an OS command injection vulnerability that allows MCP clients to bypass the command whitelist by injecting shell metacharacters into execute_command arguments. Attackers or malicious prompts can call a safe command such as pwd with arguments like ';' to run forbidden commands as the server user without approval.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

